This invention relates to thermionic cathode technology and more particularly to miniature cathodes for use in very high frequency linear beam amplifiers.
Generating small, intense electron beams and injecting them into the interaction region of terahertz vacuum electron devices such as backward wave oscillators or traveling wave tubes presents many problems. In very high frequency applications, the beam within the interaction regions of the device needs to be very small, given the small size of these devices. Conventional beam sizes are 0.020 inch to 0.100 inch diameter, which is too large.